This invention relates to an effective method of identifying a connection error for preventing errors in electrically connecting modules having various functions. This invention relates also to electronic apparatus of various kinds such as apparatus for measurements and adjustments adapted to use such a method.
Various methods for preventing connection errors have been proposed. As a method of preventing connection errors between units having same external characteristics but different in electronic specifications, Japanese Patent Publication Tokkai 11-307180, for example, described a method of reversing the male-female relationship between the connectors of two units from that of other two pairs of units such that it will be prevented for one of the two units from having the other of the other two units erroneously connected thereto.
Since it is only a matter of reversing the male-female relationship by this prior art method, it is of no use in situations where many connectors are provided to one unit and many units can be connected to each connector since there will be many combinations with the same male-female relationship.
In Japanese Patent Application Tokugan 2002-14490 filed May 20, 2002, the present inventors proposed electronic apparatus which may be produced by having many kinds of mounting substrates prepared such as substrates for input, output, power source and communication and mounting necessary ones of these substrates to a base substrate of a common type so as to obtain apparatus of desired kinds. Since such apparatus are obtained by selecting many kinds of mounting substrates with different specifications and functions selectively and mounting them to a plurality of connectors on a common base substrate, there may be situations where mounting substrates with different specifications and functions are connected in common to a same connector. In other words, any one of a plurality of different kinds of mounting substrates is selectively mounted to a connector and it is presupposed that connecting substrates of different types are adapted to be mounted to a same connector. Thus, it is not possible to use physical means of the prior art technology described above to prevent base substrates of different kinds from being mounted. Since a substrate of an incorrect kind may be mounted for producing a desired type of apparatus, it is necessary to avoid such connection errors.